Fix blob redirect handling regression

#771 broke the redirect
handling because the redirect location returned by CrateDB includes the
full path to the blob.

E.g. `http://localhost:4202/_blobs/b1/2c2bbc39c1c8b8c217c04cf5fc0dcb23c6d93b39`

With the change in the above PR, `_server_url` retained the path and the
follow up request was made to
`http://localhost:4202/_blobs/b1/2c2b.../_blobs/b1/2c2b...`, leading to
a 404 and a BlobDigestNotFound exception.

crate-qa tests failed because of that.

Author: mfussenegger

src/crate/client/http.py

@@ -637,7 +637,8 @@ def _request(self, method, path, server=None, **kwargs):
                 )
                 redirect_location = response.get_redirect_location()
                 if redirect_location and 300 <= response.status <= 308:
-                    redirect_server = _server_url(redirect_location)
+                    redirect_url = urlparse(redirect_location)
+                    redirect_server = f"{redirect_url.scheme}://{redirect_url.netloc}"
                     self._add_server(redirect_server)
                     return self._request(
                         method, path, server=redirect_server, **kwargs

tests/client/test_http.py

@@ -170,7 +170,7 @@ def test_redirect_handling():
     gets added to the server pool.
     """
     with patch(
-        REQUEST_PATH, return_value=fake_redirect("http://localhost:4201")
+        REQUEST_PATH, return_value=fake_redirect("http://localhost:4201/_blobs/blobs/fake_digest")
     ):
         client = Client(servers="localhost:4200")